Issue No. 10 - Oct. (2013 vol. 19)
DOI Bookmark: http://doi.ieeecomputersociety.org/10.1109/TVCG.2012.151
Baoquan Liu , Dept. of Comput. Sci. & Technol., Univ. of Bedfordshire, Luton, UK
G. J. Clapworthy , Dept. of Comput. Sci. & Technol., Univ. of Bedfordshire, Luton, UK
Feng Dong , Dept. of Comput. Sci. & Technol., Univ. of Bedfordshire, Luton, UK
E. C. Prakash , Dept. of Comput. Sci. & Technol., Univ. of Bedfordshire, Luton, UK
We present a novel approach for GPU-based high-quality volume rendering of large out-of-core volume data. By focusing on the locations and costs of ray traversal, we are able to significantly reduce the rendering time over traditional algorithms. We store a volume in an octree (of bricks); in addition, every brick is further split into regular macrocells. Our solutions move the branch-intensive accelerating structure traversal out of the GPU raycasting loop and introduce an efficient empty-space culling method by rasterizing the proxy geometry of a view-dependent cut of the octree nodes. This rasterization pass can capture all of the bricks that the ray penetrates in a per-pixel list. Since the per-pixel list is captured in a front-to-back order, our raycasting pass needs only to cast rays inside the tighter ray segments. As a result, we achieve two levels of empty space skipping: the brick level and the macrocell level. During evaluation and testing, this technique achieved 2 to 4 times faster rendering speed than a current state-of-the-art algorithm across a variety of data sets.
Octrees, Graphics processing unit, Rendering (computer graphics), Acceleration, Interpolation, Cameras, Casting
Baoquan Liu, G. J. Clapworthy, Feng Dong and E. C. Prakash, "Octree Rasterization: Accelerating High-Quality Out-of-Core GPU Volume Rendering," in IEEE Transactions on Visualization & Computer Graphics, vol. 19, no. 10, pp. 1732-1745, 2013.